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Stockholders' Equity, Stock Award and Incentive Plan (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Stock Award and Incentive Plan [Abstract] |  |  |
Number of common stock available for issuance (in shares) | 880,000 |  |
Term of stock options granted under Plan | 10 years |  |
Vesting period, generally, for stock options granted under the plan | 3 years |  |
Shares Available for Grant [Roll Forward] |  |  |
Balance, beginning of year (in shares) | 1,036,505 | 1,202,426 | 1,491,965
Granted (in shares) | (260,508) | (257,072) | (538,787)
Exercised/vested (in shares) | 0 | 0 | 0
Canceled (in shares) | 90,026 | 91,151 | 249,248
Balance, end of year (in shares) | 866,023 | 1,036,505 | 1,202,426
Stock Options [Member] |  |  |
Stock Options [Roll Forward] |  |  |
Balance, beginning of year (in shares) | 996,839 | 1,198,725 | 1,091,844
Granted (in shares) | 191,147 | 187,533 | 383,622
Exercised/vested (in shares) | (98,945) | (353,636) | (150,944)
Canceled (in shares) | (34,782) | (35,783) | (125,797)
Balance, end of year (in shares) | 1,054,259 | 996,839 | 1,198,725
Weighted Average Exercise Price Per Share [Abstract] |  |  |
Balance, beginning of year (in dollars per share) | $ 48.21 | $ 41.66 | $ 42.29
Granted (in dollars per share) | 76.09 | 77.99 | 38.59
Exercised/vested (in dollars per share) | 33.83 | 41.56 | 36.66
Canceled (in dollars per share) | 65.74 | 50.47 | 43.78
Balance, end of year (in dollars per share) | $ 54.04 | $ 48.21 | $ 41.66
Restricted Stock [Member] |  |  |
Restricted Stock [Roll Forward] |  |  |
Balance, beginning of year (in shares) | 180,110 | 227,213 | 284,245
Granted (in shares) | 69,361 | 69,539 | 155,165
Exercised/vested (in shares) | (59,649) | (61,274) | (88,746)
Canceled (in shares) | (55,244) | (55,368) | (123,451)
Balance, end of year (in shares) | 134,578 | 180,110 | 227,213
Weighted Average Exercise Price Per Share [Abstract] |  |  |
Balance, beginning of year (in dollars per share) | $ 58.57 | $ 49.57 | $ 58.63
Granted (in dollars per share) | 76.26 | 78.00 | 38.37
Exercised/vested (in dollars per share) | 56.44 | 52.51 | 57.38
Canceled (in dollars per share) | 58.57 | 52.74 | 50.72
Balance, end of year (in dollars per share) | $ 68.64 | $ 58.57 | $ 49.57

X
- Definition The number of additional shares authorized during the period which increased the number of shares available for grant under the plan at the end of the reporting period. + References No definition available. + Details
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- Definition The number of shares cancelled during the period which increased the shares available for grant under the plan at the end of the reporting period. + References No definition available. + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3)-(4) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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